拍品描述： China 1897 Imperial Chinese Post 50c. black-green error of colour in a block of four with interpanneau margin at right, part original gum. A rare and highly desirable block, only 240 stamps are reported as being sold and any multiple is of the upmost rarity. Experts and Consultants certificate (2016) which suggest a small tone spot on the lower right stamp, but this was only a fragment of paper which has now been removed. Chan 100a; S.G. 104b. Photo